Next Article in Journal
The Profile, Health Seeking Behavior, Referral Patterns, and Outcome of Outborn Neonates Admitted to a District and Regional Hospital in the Upper West Region of Ghana: A Cross-Sectional Study
Previous Article in Journal
Prevalence and Selected Sociodemographic of Movement Behaviors in Schoolchildren from Low- and Middle-Income Families in Nanjing, China: A Cross-Sectional Questionnaire Survey
Previous Article in Special Issue
New and Emerging Targeted Therapies for Pediatric Acute Myeloid Leukemia (AML)
Open AccessReview

Harnessing T Cells to Target Pediatric Acute Myeloid Leukemia: CARs, BiTEs, and Beyond

Department of Oncology, St. Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, TN 77030, USA
Department of Bone Marrow Transplantation and Cellular Therapy, St. Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, TN 77030, USA
Author to whom correspondence should be addressed.
Children 2020, 7(2), 14;
Received: 15 January 2020 / Revised: 3 February 2020 / Accepted: 4 February 2020 / Published: 17 February 2020


Outcomes for pediatric patients with acute myeloid leukemia (AML) remain poor, highlighting the need for improved targeted therapies. Building on the success of CD19-directed immune therapy for acute lymphocytic leukemia (ALL), efforts are ongoing to develop similar strategies for AML. Identifying target antigens for AML is challenging because of the high expression overlap in hematopoietic cells and normal tissues. Despite this, CD123 and CD33 antigen targeted therapies, among others, have emerged as promising candidates. In this review we focus on AML-specific T cell engaging bispecific antibodies and chimeric antigen receptor (CAR) T cells. We review antigens being explored for T cell-based immunotherapy in AML, describe the landscape of clinical trials upcoming for bispecific antibodies and CAR T cells, and highlight strategies to overcome additional challenges facing translation of T cell-based immunotherapy for AML.
Keywords: acute myeloid leukemia; immunotherapy; chimeric antigen receptor; CAR; bispecific antibodies; BiTE; DART acute myeloid leukemia; immunotherapy; chimeric antigen receptor; CAR; bispecific antibodies; BiTE; DART

1. Introduction

Despite advances in therapy, prognosis continues to be poor for patients with acute myeloid leukemia (AML) [1]. Targeted immunotherapy has the potential to improve outcome for this patient population while avoiding the long term toxicities associated with conventional chemotherapy. CD19-directed therapies for pediatric acute lymphocytic leukemia (ALL) have generated impressive responses and led to United States Food and Drug Administration (FDA) approval [2,3,4]. However, advancing immunotherapeutic strategies for AML has been hindered by additional challenges such as overlapping antigen expression on AML blasts and healthy tissues, T-cell persistence, and an immunosuppressive microenvironment.
There are several immunotherapeutic strategies that have been developed for AML such as monoclonal antibodies [5], checkpoint inhibitors [6], cancer vaccines, natural killer cell add-back [7], and T cell-based therapies [8,9]. In this review, we will focus on strategies that target T cells to AML blasts, specifically highlighting bispecific antibodies and chimeric antigen receptor (CAR) T cells (Figure 1). We will discuss identification of target antigens applicable across T cell-based immunotherapies, review current and upcoming clinical trials, and identify challenges for T cell-based immunotherapies in AML and strategies to address them.
Bispecific antibodies are molecules with distinct recognition domains recognizing both a specific tumor antigen on the AML blasts and CD3 on resident T cells [10]. By activating T cells and bringing them in contact with blasts at the immunologic synapse, they induce anti-leukemic cytotoxicity. In contrast, CAR T cells are generated by collecting T cells from a patient, genetically engineering them to express a CAR recognizing a specific tumor antigen, expanding the T cells ex vivo, and infusing them back into the patient [11]. Chimeric antigen receptors consist of an antigen recognition domain, traditionally from the single chain variable fragment of an antibody, hinge and transmembrane components, costimulatory domains, and an activation domain derived from the CD3ζ portion of the TCR [11]. While initial clinical experience has been primarily in adult patients with AML, clinical trials for pediatric patients are becoming available (Table 1, Table 2).

2. Identifying Target Antigens

Ideal antigens for cell-based immunotherapy are those that are expressed at high levels on malignant cells and absent or at low levels on normal tissues. Because of the challenge of identifying these differentially expressed targets, integrated screening efforts have been used in order to determine candidate antigens for targeted immunotherapy in AML [12]. Because of the relative heterogeneity of AML and overlap with hematopoietic progenitor cells or mature myeloid cells, it is likely that combinatorial therapies or advanced design techniques will be necessary to advance targeted T cell-based immunotherapy for AML. Most bispecific antibodies and CAR T cells currently being explored recognize antigens expressed on the cell surface only, which limits the pool of potential targets [10,13,14]. CD123 and CD33 are two of the antigens being explored currently as targets for bispecific antibodies and CARs (Table 1, Table 2). We discuss these along with other antigens currently under preclinical and clinical investigation. Strategies being translated to the clinic will be further discussed in Section 3 and Section 4.

2.1. Antigens with Overlapping Expression in AML Blasts, Leukemic Stem Cells and Normal Hematopoietic Progenitor Cells

CD123 or IL3Ra is a glycoprotein composed of the alpha subunit of the interleukin-3 receptor. It is widely expressed in hematologic malignancies including AML [15], both on differentiated leukemic blasts and leukemic stem cells [16], which makes CD123 an attractive immunotherapy target. A notable consideration for CD123 targeted immunotherapy is the concomitant low expression of CD123 on normal hematopoietic progenitor cells (HPCs), and mature cells of the myeloid lineage [17,18]. CD123 is also expressed at low levels on endothelial cells [19], which should lead to close monitoring for on-target off-tumor toxicity such as capillary leak syndrome (CLS). More recently, overexpression of CD123 has been described in high risk pediatric AML cases [20].
FMS-like tyrosine kinase 3 (FLT3), also known as CD135, belongs to the receptor tyrosine kinase class III family and is uniformly expressed on AML blasts, both those with wild type FLT3 and with internal tandem duplication (FLT3-ITD) [21,22]. Like CD123, FLT3 is also expressed on HPCs and other early progenitors [23].

2.2. Antigens Primarily Overlapping with Mature Hematopoietic Cells

CD33 is a transmembrane sialic acid-binding immunoglobulin-type lectin (SIGLEC) receptor expressed on AML blasts [24]. CD33 also has expression on hematopoietic progenitor cells, in addition to mature myeloid cells, which must be taken into account when considering on-target off-tumor toxicity [24]. CD33 is also expressed on myeloid-derived suppressor cells in the AML microenvironment, cells that promote an immunosuppressive microenvironment and dampen the effect of T-cell mediated killing [25]. Therefore, targeting CD33 has the potential to enhance anti-leukemic activity not only by direct cytotoxicity, but also by generating a more favorable microenvironment to promote T-cell activity. In addition to hematopoietic cells, CD33 is expressed on hepatic Kupffer cells [24], raising concerns for its role in hepatic toxicity and sinusoidal obstruction syndrome with previously used CD33-directed therapies [26].
C-type lectin-like receptor 1 (CLL1, also CLEC12A) is highly expressed in AML. CLL-1 is absent from hematopoietic progenitor cells but is present on mature myeloid cells [27], and is a potential therapeutic target.
CD70 is an immune checkpoint molecule identified on AML blasts, in addition to traditional antigen presenting cells [12,28]. CD70 has recently been described as a CAR T-cell target for AML, showing promising preclinical activity [29,30].
While the antigens mentioned in Section 2.1 and Section 2.2 are attractive given their wide expression on AML blasts, clinical targeting of these antigens requires thoughtful combinatorial therapies to avoid excessive myelotoxicity. Potential strategies for clinical application include bridging to hematopoietic stem cell transplant or additional engineering strategies.

2.3. Antigens Present on Multiple Tumor Types

Folate receptors are upregulated on an array of malignancies, both on the surface of tumor cells and on surrounding stroma and tumor-associated macrophages [31]. The folate receptor beta (FRβ) isoform is expressed on AML blasts [31,32,33]. FRβ CAR T-cell therapy has been investigated preclinically for AML and pediatric solid tumors [32,33,34].
NKG2D is a naturally occurring receptor present on NK cells and some T-cell subsets, which recognizes antigens on the tumor surface. In order to capitalize on this tumor specificity, NKG2D receptors have been used as antigen recognition domains for CAR and other T-cell engaging modalities [35,36,37].
Lewis Y is a tumor-associated antigen expressed on hematologic malignancies including AML and multiple myeloma, in addition to several epithelial solid tumors [38,39], and has been investigated as a target for CAR T-cell therapy [40].

2.4. Epitope-Specific Antigens

CD44 is a ubiquitously expressed membrane glycoprotein, which is overexpressed on several hematologic and solid malignancies but also healthy tissues such as lung, kidney, and gastrointestinal tract [41]. However, the CD44v6 isoform noted in AML and multiple myeloma is relatively tumor restricted [41], making isoform-specific targeting a potential immunotherapeutic strategy.
CD43 is a sialomucin transmembrane molecule universally expressed on leukocytes [42]. CD43s is a unique sialylated epitope, overexpressed in AML and only weakly expressed on normal myeloid cells [42]. A bispecific T-cell engaging antibody utilizing CD43s to selectively target AML blasts while sparing normal leukocytes has shown preclinical activity [43].

2.5. Antigens Present in Distinct AML Subsets

CD7 is a transmembrane glycoprotein molecule present on thymocytes and mature T cells that is important for T-cell interactions and differentiation [44]. CD7 is highly expressed in T-ALL [45,46]. It is also expressed in approximately 30% of patients with AML and has been correlated with low expression of wild type CEBPA and a worse prognosis [47,48,49,50,51,52,53], making it an attractive immunotherapeutic target. However, because it is also expressed on most mature T cells, additional engineering and processing techniques are necessary to avoid fratricide when using T cell-based therapies to target CD7 [54].
Leukocyte immunoglobulin-like receptor-B4 (LILRB4) is a protein highly expressed in monocytic AML (formerly M5 according to the French-American-British classification), a subset accounting for 20% of pediatric cases [55]. Preclinical studies of CAR T cells targeting LILRB4 have shown antitumor efficacy without toxicity against hematopoietic progenitor cells [56].
CD19 is a B-cell marker associated with B-ALL, that is also expressed in a small subset of patients with AML and mixed-phenotype acute leukemia, associated with t(8;21), who may benefit from CD19-directed therapies [57].

2.6. Intracellular Antigens

PR1 is an HLA-A2 restricted AML nonapeptide derived from neutrophil elastase (NE) and proteinase-3 (P3), which offers AML specificity but is only present in patients expressing HLA-A2 [58]. A bispecific T-cell engaging antibody has been developed targeting the PR1/HLA-A2 complex, which has shown preclinical efficacy and may be clinically applicable for a subset of patients [59].
Wilms Tumor 1 (WT1) is a zinc-finger transcription factor, which is an intracellular tumor-associated antigen which has limited low-level expression on normal tissues but is overexpressed in many hematologic and solid malignancies [60]. WT1 is overexpressed in AML, particularly in patients with poor prognosis. Because of its intracellular localization, WT1 cannot be targeted with traditional CARs or bispecific antibodies. However, WT1-derived peptides presented by HLA molecules can be targeted with T-cell receptors (TCRs) or CARs and bispecific antibodies that recognize HLA/WT1 peptide complexes [60,61].

3. Bispecific Antibody Clinical Development

Bispecific antibodies are antibodies that in general terms redirect an immune cell to a cancer cell by simultaneously targeting one antigen expressed on cancer cells (e.g., CD123, CD19) and one on immune cells (e.g., CD3, CD16). They vary in size, kinetics, and activity depending on their structure [10]. Strategies incorporating the immunoglobulin fragment crystallizable (Fc) domain have a longer half-life, but risk attracting macrophages that can hinder interactions at the immunologic synapse [62]. Approaches that do not incorporate an Fc domain may allow for less hindrance at the synapse, but have a shorter half-life [10]. Two of the better known strategies for the latter group include bispecific engager molecules (BiTE) and dual affinity retargeting antibodies (DART). A BiTE is a small molecule containing two different antigen recognition sequences bound by a short, flexible linker [10,63]. A DART also incorporates two single chain variable fragments (scFv) joined by a disulfide bond, which impacts steric interactions at the immunologic synapse [64].
Optimization of bispecific antibodies is ongoing in order to improve effectivity of these products in clinical application. Current clinical trials utilizing these strategies are listed in Table 1.
Designs for CD3×CD33 under current preclinical and early clinical research include traditional BiTEs, full-length bispecific antibodies, and trivalent or tetramer products with additional antigen recognition domains [25,63,65,66,67,68,69]. Preliminary clinical results for AMV564, a CD3×CD33 tandem diabody showed antileukemic activity in three of the first nine evaluable patients with no dose limiting toxicities identified, and has been granted orphan drug status by the FDA (FDA) [70].
CD3×CD123 targeting strategies include full length antibodies and DARTs [64,71]. Flotetuzumab, a CD3×D123 DART, has shown clinical activity in adults, and is now the first bispecific antibody for AML being studied in pediatric patients (Table 1). In addition to CD33 and CD123, CD3×CLL1 bispecific antibodies have shown preclinical activity [62,72,73] and are being evaluated in an ongoing phase 1 study (NCT03038230). FLT3×CD3 bispecific antibodies have shown preclinical efficacy, in addition to FLT3 CAR T cells which is discussed in Section 4 [74].

4. CAR T Cell Clinical Development

CAR T cells harness the specificity of an antibody and the cytotoxic activity of a T cell to provided targeted antitumor activity. In addition to antigen selection as discussed in Section 2, variations in each of the other CAR components can also impact activity. Intrinsic T-cell factors and additional modifications to the CAR T cells can modulate the antitumor activity and impact persistence, as previously reviewed [75].
Several groups have shown preclinical efficacy of CD123-CAR T cells [76,77,78,79,80,81,82,83,84], and these constructs have transitioned to early clinical investigation with encouraging initial results (Table 2) [85]. This has resulted in orphan drug designation by the FDA for the Mustang Bio CD123-CAR MB-102, currently under investigation at City of Hope Medical Center. Given anticipated on-target off-tumor activity against HPCs, CD123-CAR T cell trials have incorporated additional measures to ensure safety, including incorporating bridge-to-transplant options and safety switches to “turn off” CAR T cells after desired activity to avoid toxicity to infused HPCs after bone marrow transplant [77,79].
CD33-CAR T-cell strategies have also shown efficacy in preclinical models and are being translated to clinical application [24,79,86,87,88,89,90]. Like CD123-CAR T cells, there is potential that these will require a bridge-to-transplant strategy in the case of toxicity against HPCs. In addition to safety switches [77], an alternative strategy being explored to circumvent the challenge of expression on normal myeloid cells is genetic inactivation of CD33 in hematopoietic cells is to combine CD33-targeting T cells with CD33- hematopoietic stem cell transplant, which has shown feasibility in non-human primate models and is under further clinical development [91].
CAR T-cells targeting NKG2D have shown preclinical efficacy [36,92]. NKG2D-CAR T cells were investigated in a phase 1 clinical trial including seven patients with AML and five patients with multiple myeloma and demonstrated safety but no disease response [35]. Lack of response was attributed to poor CAR T-cell expansion and persistence, and work is ongoing to modify NKG2D CAR T cells to improve persistence [35]. A case report of NKG2D-CAR T cells did show antitumor efficacy in a single patient [93].
A phase 1 study of CAR T-cells targeting Lewis Y demonstrated safety and in some patients transient anti-leukemic activity, but no durable response despite persistence of infused CAR T cells [40]. CLL1-CAR T cells have shown preclinical efficacy [27,94] in AML and is in ongoing clinical development. There are ongoing clinical studies in China targeting CLL1 in combination with other AML antigens [95].
A clinical trial of FLT3-CAR T cells is also underway based on promising preclinical data [74,96,97]. It has been shown preclinically that FLT3 surface expression can be increased by simultaneous administration of tyrosine kinase inhibitors. This in turn can potentiate the effect of FLT3-directed immune therapy when used in combination [97,98].

5. Additional T Cell-Based Immunotherapy Strategies

5.1. Bispecific T-Cell Engager Secreting Cells

Because administration of bispecific antibodies can be limited by their short half-life, systemic effects, and reliance on native donor effector cells, groups have explored strategies to engineer cells to secrete bispecific antibodies. For example, T cells secreting CD123- or CLL1-specific BiTEs (Engager T cells) have anti-AML activity in preclinical models [99,100]. One advantage of engineering T cells to secrete BiTEs is that these cells can be further genetically modified to express costimulatory molecules or chimeric cytokine receptors [99,101]. Additionally, investigators have explored the anti-AML activity of engineered mesenchymal stromal cells that secrete CD33xCD3 bispecific antibodies in preclinical models [102,103].

5.2. T Cell Receptor Engineered T Cells

To overcome the limitation of recognizing only surface antigens on tumor cells, an alternative strategy is to engineer a specific TCRs, which allows for the recognition of intracellular proteins on MHC [60]. Because this strategy uses an MHC-dependent recognition strategy, the products are HLA-specific and therefore each product will be applicable to only a subset of patients whose blasts express a given antigen. TCR therapy targeting WT1 has shown promise in preventing relapse after HCT for AML in adults [61].

5.3. Tumor-Associated Antigen Specific T Cells

Patients with AML have naturally occurring tumor-reactive T cells, though often without appropriate quantity or activity to control disease [104]. In contrast to direct genetic modification, it is possible to select for and expand donor-derived naturally occurring T cells against multi tumor specific antigens. This strategy is being explored in early clinical studies (NCT02494167) [105].

6. Challenges of Bispecific Antibody and CAR T-Cell Therapies

6.1. Toxicity

Bispecific antibodies and CAR T cells show promise in improving outcomes for patients with AML. However, there are additional challenges to overcome for successful clinical application. A comprehensive discussion of these challenges is beyond the scope of this discussion but have been recently reviewed as outlined. In addition to the on-target off-tumor toxicities discussed in Section 1, cytokine release syndrome and immune effector cell associated neurotoxicity syndrome have been described after CAR T infusion and appear to be generalized phenomena across multiple target antigens and tumor types [106]. Similar phenomena are described with bispecific antibodies [107].

6.2. Immune Escape

A major mechanism of relapse after targeted T cell-based therapies is antigen escape, which has been described with both CAR T cell and antibody-based CD19-directed therapy [108,109]. Given the heterogeneity of AML, this challenge is likely to be amplified with targeted therapy for AML [110]. One strategy to prevent antigen escape is targeting multiple antigens simultaneously to add selective pressure. Development of bispecific CAR T cells targeting CD123 and CD33 is ongoing [111].

6.3. AML Microenvironment

In AML, the immune suppressive microenvironment plays an important role in both primary therapeutic resistance and relapse in T cell-based therapies [112]. Immune suppressive cells including regulatory T cells [113,114] and myeloid-derived suppressor cells [115,116] among others can inhibit T-cell function and contribute to exhaustion. Anti-inflammatory cytokines including IL10 [117] and TGF-β [118] contribute to a suppressive environment, along with metabolic alterations [119,120]. Combination therapeutics and additional genetic modifications to T cells are potential strategies to modulate the environment to one that promotes anti-leukemic activity of modified T cells [59,121].

7. Conclusions

Targeted T cell-based immunotherapies offer great promise for AML therapy, but still face challenges in clinical application. Bispecific antibodies offer potential for use as an off-the-shelf product, though are limited by impact of half-life on administration and reliance on native host immune system for effector function. CAR T cells retain the specificity of antibodies with enhanced effector function, though there are additional challenges related to production and persistence of cellular therapy products. CD123 and CD33 stand out as promising antigens, though there are several others under investigation. Overcoming toxicities related to shared expression of target antigens on normal hematopoietic cells will be key in translating these therapies. Ongoing early clinical studies are being performed in patients with AML who have relapsed/refractory disease. However, as the field advances we will get a better understanding of the safety profile and efficacy of these therapies. This will allow devising clinical trials in the upfront setting, similar to CD19- and CD22-directed immunotherapies for ALL [122,123]. We are hopeful that synthesizing the lessons learned from the development of an array of antibody- and T cell-based targeted immunotherapies will help to swiftly advance the care for patients with AML going forward.

Author Contributions

All authors have read and agree to the published version of the manuscript. R.E. and M.P.V. conceptualized the manuscript. R.E. prepared the original draft. M.P.V. and S.G. reviewed and edited.


The authors’ AML research was/is supported by grants from the Leukemia and Lymphoma Society, Alex Lemonade Stand Foundation, St. Baldrick’s Foundation, the Cancer Prevention Research Institute of Texas (RP160693), Assisi Foundation of Memphis, and American Lebanese Syrian Associated Charities (ALSAC).

Conflicts of Interest

S.G. and M.P.V. hold patent applications in the field of gene and cell therapy.


  1. Zwaan, C.M.; Kolb, E.A.; Reinhardt, D.; Abrahamsson, J.; Adachi, S.; Aplenc, R.; De Bont, E.S.; De Moerloose, B.; Dworzak, M.; Gibson, B.E.; et al. Collaborative efforts driving progress in pediatric acute myeloid leukemia. J. Clin. Oncol. 2015, 33, 2949–2962. [Google Scholar] [CrossRef] [PubMed]
  2. Jen, E.Y.; Xu, Q.; Schetter, A.; Przepiorka, D.; Shen, Y.L.; Roscoe, D.; Sridhara, R.; Deisseroth, A.; Philip, R.; Farrell, A.T.; et al. FDA approval: Blinatumomab for patients with B-cell precursor acute lymphoblastic leukemia in morphologic remission with minimal residual disease. Clin. Cancer Res. 2019, 25, 473–477. [Google Scholar] [CrossRef] [PubMed]
  3. O’Leary, M.C.; Lu, X.; Huang, Y.; Lin, X.; Mahmood, I.; Przepiorka, D.; Gavin, D.; Lee, S.; Liu, K.; George, B.; et al. FDA approval summary: Tisagenlecleucel for treatment of patients with relapsed or refractory B-cell precursor acute lymphoblastic leukemia. Clin. Cancer Res. 2019, 25, 1142–1146. [Google Scholar] [CrossRef] [PubMed]
  4. Bouchkouj, N.; Kasamon, Y.L.; de Claro, R.A.; George, B.; Lin, X.; Lee, S.; Blumenthal, G.M.; Bryan, W.; McKee, A.E.; Pazdur, R. FDA Approval Summary: Axicabtagene Ciloleucel for Relapsed or Refractory Large B-cell Lymphoma. Clin. Cancer Res. 2019, 25, 1702–1708. [Google Scholar] [CrossRef]
  5. Mahalleh, M.; Shabani, M.; Rayzan, E.; Rezaei, N. Reinforcing the primary immunotherapy modulators against acute leukemia; monoclonal antibodies in AML. Immunotherapy 2019. [Google Scholar] [CrossRef]
  6. Davis, K.L.; Agarwal, A.M.; Verma, A.R. Checkpoint inhibition in pediatric hematologic malignancies. Pediatr. Hematol. Oncol. 2017, 34, 379–394. [Google Scholar] [CrossRef] [PubMed]
  7. Hansrivijit, P.; Gale, R.P.; Barrett, J.; Ciurea, S.O. Cellular therapy for acute myeloid Leukemia—Current status and future prospects. Blood Rev. 2019, 37, 100578. [Google Scholar] [CrossRef]
  8. Liu, Y.; Bewersdorf, J.P.; Stahl, M.; Zeidan, A.M. Immunotherapy in acute myeloid leukemia and myelodysplastic syndromes: The dawn of a new era? Blood Rev. 2019, 34, 67–83. [Google Scholar] [CrossRef]
  9. Bonifant, C.L.; Velasquez, M.P.; Gottschalk, S. Advances in immunotherapy for pediatric acute myeloid leukemia. Expert Opin. Biol. Ther. 2018, 18, 51–63. [Google Scholar] [CrossRef]
  10. Brinkmann, U.; Kontermann, R.E. The making of bispecific antibodies. MAbs 2017, 9, 182–212. [Google Scholar] [CrossRef]
  11. Sadelain, M.; Brentjens, R.; Riviere, I. The basic principles of chimeric antigen receptor design. Cancer Discov. 2013, 3, 388–398. [Google Scholar] [CrossRef] [PubMed]
  12. Perna, F.; Berman, S.; Soni, R.; Mansilla-Soto, J.; Eyguem, J.; Hamieh, M.; Hendrickson, R.; Brennan, C.; Sadelain, M. Integrating proteomics and transcriptomics for systematic combinatorial chimeric antigen receptor therapy of AML. Cancer Cell 2017, 32, 506–519. [Google Scholar] [CrossRef] [PubMed]
  13. Riviere, I.; Sadelain, M. Chimeric antigen receptors: A cell and gene therapy perspective. Mol. Ther. 2017, 25, 1117–1124. [Google Scholar] [CrossRef] [PubMed]
  14. Salter, A.I.; Pont, M.J.; Riddell, S.R. Chimeric antigen receptor-modified T cells: CD19 and the road beyond. Blood 2018, 131, 2621–2629. [Google Scholar] [CrossRef] [PubMed]
  15. Ehninger, A.; Kramer, M.; Rollig, C.; Thiede, C.; Bornhauser, M.; von Bonin, M.; Wermke, M.; Feldmann, A.; Bachmann, M.; Ehninger, G.; et al. Distribution and levels of cell surface expression of CD33 and CD123 in acute myeloid leukemia. Blood Cancer J. 2014, 4, e218. [Google Scholar] [CrossRef]
  16. Jordan, C.T.; Upchurch, D.; Szilvassy, S.J.; Guzman, M.L.; Howard, D.S.; Pettigrew, A.L.; Meyerrose, T.; Rossi, R.; Grimes, B.; Rizzieri, D.A.; et al. The interleukin-3 receptor alpha chain is a unique marker for human acute myelogenous leukemia stem cells. Leukemia 2000, 14, 1777–1784. [Google Scholar] [CrossRef] [PubMed]
  17. Sato, N.; Caux, C.; Kitamura, T.; Watanabe, Y.; Arai, K.; Banchereau, J.; Miyajima, A. Expression and factor-dependent modulation of the interleukin-3 receptor subunits on human hematopoietic cells. Blood 1993, 82, 752–761. [Google Scholar] [CrossRef]
  18. Testa, U.; Fossati, C.; Samoggia, P.; Masciulli, R.; Mariani, G.; Hassan, H.J.; Sposi, N.M.; Guerriero, R.; Rosato, V.; Gabbianelli, M.; et al. Expression of growth factor receptors in unilineage differentiation culture of purified hematopoietic progenitors. Blood 1996, 88, 3391–3406. [Google Scholar] [CrossRef]
  19. Sun, Y.; Wang, S.; Zhao, L.; Zhang, B.; Chen, H. IFN-γ andTNF-α aggravate endothelial damage caused by CD123-targeted CAR T cell. Onco Targets Ther. 2019, 12, 4907–4925. [Google Scholar] [CrossRef]
  20. Lamble, A.; Brodersen, L.; Alonzo, T.A.; Wang, J.; Gerbing, R.; Pardo, L.; Sung, L.; Tasian, S.; Cooper, T.; Kolb, E.; et al. Correlation of CD123 expression lebel with disease characteristics and outcomes in pediatric acute myeloid leukemia: A report from the children’s oncology group. Blood 2019, 134, 459. [Google Scholar] [CrossRef]
  21. Rosnet, O.; Buhring, H.J.; Marchetto, S.; Rappold, I.; Lavagna, C.; Sainty, D.; Arnoulet, C.; Chabannon, C.; Kanz, L.; Hannum, C.; et al. Human FLT3/FLK2 receptor tyrosine kinase is expressed at the surface of normal and malignant hematopoietic cells. Leukemia 1996, 10, 238–248. [Google Scholar] [PubMed]
  22. Kuchenbauer, F.; Kern, W.; Schoch, C.; Kohlmann, A.; Hiddemann, W.; Haferlach, T.; Schnittger, S. Detailed analysis of FLT3 expression levels in acute myeloid leukemia. Haematologica 2005, 90, 1617–1625. [Google Scholar] [PubMed]
  23. Kikushige, Y.; Yoshimoto, G.; Miyamoto, T.; Iino, T.; Mori, Y.; Iwasaki, H.; Niiro, H.; Takenaka, K.; Nagafuji, K.; Harada, M.; et al. Human Flt3 is expressed at the hematopoietic stem cell and the granulocyte/macrophage progenitor stages to maintain cell survival. J. Immunol. 2008, 180, 7358–7367. [Google Scholar] [CrossRef] [PubMed]
  24. Kenderian, S.; Ruella, M.; Shestova, O.; Klichinsky, M.; Aikawa, V.; Morrissette, J.; Scholler, J.; Song, D.; Porter, D.; Carroll, M.; et al. CD33-specific chimeric antigen receptor T cells exhibit potent preclinical activity against human acute myeloid leukemia. Leukemia 2015, 29, 1637–1647. [Google Scholar] [CrossRef]
  25. Jitschin, R.; Saul, D.; Braun, M.; Tohumeken, S.; Volkl, S.; Kischel, R.; Lutteropp, M.; Dos Santos, C.; Mackensen, A.; Mougiakakos, D. CD33/CD3-bispecific T-cell engaging (BiTE®) antibody construct targets monocytic AML myeloid-derived suppressor cells. J. Immunother. Cancer 2018, 6, 116. [Google Scholar] [CrossRef]
  26. Godwin, C.D.; McDonald, G.B.; Walter, R.B. Sinusoidal obstruction syndrome following CD33-targeted therapy in acute myeloid leukemia. Blood 2017, 129, 2330–2332. [Google Scholar] [CrossRef]
  27. Wang, J.; Chen, S.; Xiao, W.; Li, W.; Wang, L.; Yang, S.; Wang, W.; Xu, L.; Liao, S.; Liu, W.; et al. CAR-T cells targeting CLL-1 as an approach to treat acute myeloid leukemia. J. Hematol. Oncol. 2018, 11, 7. [Google Scholar] [CrossRef]
  28. Riether, C.; Schurch, C.M.; Buhrer, E.D.; Hinterbrandner, M.; Huguenin, A.L.; Hoepner, S.; Zlobec, I.; Pabst, T.; Radpour, R.; Ochsenbein, A.F. CD70/CD27 signaling promotes blast stemness and is a viable therapeutic target in acute myeloid leukemia. J. Exp. Med. 2017, 214, 359–380. [Google Scholar] [CrossRef]
  29. Leick, M.; Scarfo, I.; Choi, B.; Larson, R.; Bouffard, A.; Castano, A.; Cabral, M.; Schmidts, A.; Frigault, M.; Maus, M. Use of CD70 targeted chimeric antigen receptor T cells for the treatment of acute myeloid leukemia. Blood 2019, 134, 4443. [Google Scholar] [CrossRef]
  30. Sauer, T.; Parikh, K.; Rooney, C.; Omer, B.; Gottschalk, S.; Sharma, S. CD70-specific CAR T cells have potent activity against acute myeloid leukemia (AML) without HSC toxicity. Blood 2019, 134, 1932. [Google Scholar] [CrossRef]
  31. Shen, J.; Putt, K.S.; Visscher, D.W.; Murphy, L.; Cohen, C.; Singhal, S.; Sandusky, G.; Feng, Y.; Dimitrov, D.S.; Low, P.S. Assessment of folate receptor-beta expression in human neoplastic tissues. Oncotarget 2015, 6, 14700–14709. [Google Scholar] [CrossRef]
  32. Lynn, R.C.; Feng, Y.; Schutsky, K.; Poussin, M.; Kalota, A.; Dimitrov, D.S.; Powell, D.J., Jr. High-affinity FRbeta-specific CAR T cells eradicate AML and normal myeloid lineage without HSC toxicity. Leukemia 2016, 30, 1355–1364. [Google Scholar] [CrossRef]
  33. Lynn, R.C.; Poussin, M.; Kalota, A.; Feng, Y.; Low, P.S.; Dimitrov, D.S.; Powell, D.J., Jr. Targeting of folate receptor beta on acute myeloid leukemia blasts with chimeric antigen receptor-expressing T cells. Blood 2015, 125, 3466–3476. [Google Scholar] [CrossRef]
  34. Lu, Y.J.; Chu, H.; Wheeler, L.W.; Nelson, M.; Westrick, E.; Matthaei, J.F.; Cardle, I.I.; Johnson, A.; Gustafson, J.; Parker, N.; et al. Preclinical evaluation of bispecific adaptor molecule controlled folate receptor CAR-T cell therapy with special focus on pediatric malignancies. Front. Oncol. 2019, 9, 151. [Google Scholar] [CrossRef]
  35. Baumeister, S.H.; Murad, J.; Werner, L.; Daley, H.; Trebeden-Negre, H.; Gicobi, J.K.; Schmucker, A.; Reder, J.; Sentman, C.L.; Gilham, D.E.; et al. Phase I trial of autologous CAR T cells targeting NKG2D ligands in patients with AML/MDS and multiple myeloma. Cancer Immunol. Res. 2019, 7, 100–112. [Google Scholar] [CrossRef]
  36. Zhang, T.; Barber, A.; Sentman, C.L. Generation of antitumor responses by genetic modification of primary human T cells with a chimeric NKG2D receptor. Cancer Res. 2006, 66, 5927–5933. [Google Scholar] [CrossRef]
  37. Marklin, M.; Hagelstein, I.; Koerner, S.P.; Rothfelder, K.; Pfluegler, M.S.; Schumacher, A.; Grosse-Hovest, L.; Jung, G.; Salih, H.R. Bispecific NKG2D-CD3 and NKG2D-CD16 fusion proteins for induction of NK and T cell reactivity against acute myeloid leukemia. J. Immunother. Cancer 2019, 7, 143. [Google Scholar] [CrossRef]
  38. Peinert, S.; Prince, H.M.; Guru, P.M.; Kershaw, M.H.; Smyth, M.J.; Trapani, J.A.; Gambell, P.; Harrison, S.; Scott, A.M.; Smyth, F.E.; et al. Gene-modified T cells as immunotherapy for multiple myeloma and acute myeloid leukemia expressing the lewis Y antigen. Gene Ther. 2010, 17, 678–686. [Google Scholar] [CrossRef]
  39. Westwood, J.A.; Smyth, M.J.; Teng, M.W.; Moeller, M.; Trapani, J.A.; Scott, A.M.; Smyth, F.E.; Cartwright, G.A.; Power, B.E.; Honemann, D.; et al. Adoptive transfer of T cells modified with a humanized chimeric receptor gene inhibits growth of Lewis-Y-expressing tumors in mice. Proc. Natl. Acad. Sci. USA 2005, 102, 19051–19056. [Google Scholar] [CrossRef]
  40. Ritchie, D.S.; Neeson, P.J.; Khot, A.; Peinert, S.; Tai, T.; Tainton, K.; Chen, K.; Shin, M.; Wall, D.M.; Honemann, D.; et al. Persistence and efficacy of second generation CAR T cell against the LeY antigen in acute myeloid leukemia. Mol. Ther. 2013, 21, 2122–2129. [Google Scholar] [CrossRef]
  41. Casucci, M.; Nicolis di Robilant, B.; Falcone, L.; Camisa, B.; Norelli, M.; Genovese, P.; Gentner, B.; Gullotta, F.; Ponzoni, M.; Bernardi, M.; et al. CD44v6-targeted T cells mediate potent antitumor effects against acute myeloid leukemia and multiple myeloma. Blood 2013, 122, 3461–3472. [Google Scholar] [CrossRef] [PubMed]
  42. Gillissen, M.A.; de Jong, G.; Kedde, M.; Yasuda, E.; Levie, S.E.; Moiset, G.; Hensbergen, P.J.; Bakker, A.Q.; Wagner, K.; Villaudy, J.; et al. Patient-derived antibody recognizes a unique CD43 epitope expressed on all AML and has antileukemia activity in mice. Blood Adv. 2017, 1, 1551–1564. [Google Scholar] [CrossRef] [PubMed]
  43. Bartels, L.; de Jong, G.; Gillissen, M.A.; Yasuda, E.; Kattler, V.; Bru, C.; Fatmawati, C.; van Hal-van Veen, S.E.; Cercel, M.G.; Moiset, G.; et al. A chemo-enzymatically linked bispecific antibody retargets T cells to a sialylated epitope on CD43 in acute myeloid leukemia. Cancer Res. 2019, 79, 3372–3382. [Google Scholar] [CrossRef] [PubMed]
  44. Haynes, B.F.; Eisenbarth, G.S.; Fauci, A.S. Human lymphocyte antigens: Production of a monoclonal antibody that defines functional thymus-derived lymphocyte subsets. Proc. Natl. Acad. Sci. USA 1979, 76, 5829–5833. [Google Scholar] [CrossRef] [PubMed]
  45. Khalidi, H.S.; Chang, K.L.; Medeiros, L.J.; Brynes, R.K.; Slovak, M.L.; Murata-Collins, J.L.; Arber, D.A. Acute lymphoblastic leukemia. Survey of immunophenotype, French-American-British classification, frequency of myeloid antigen expression, and karyotypic abnormalities in 210 pediatric and adult cases. Am. J. Clin. Pathol. 1999, 111, 467–476. [Google Scholar] [CrossRef] [PubMed]
  46. Patel, J.L.; Smith, L.M.; Anderson, J.; Abromowitch, M.; Campana, D.; Jacobsen, J.; Lones, M.A.; Gross, T.G.; Cairo, M.S.; Perkins, S.L. The immunophenotype of T-lymphoblastic lymphoma in children and adolescents: A Children’s Oncology Group report. Br. J. Haematol. 2012, 159, 454–461. [Google Scholar] [CrossRef] [PubMed]
  47. Kita, K.; Miwa, H.; Nakase, K.; Kawakami, K.; Kobayashi, T.; Shirakawa, S.; Tanaka, I.; Ohta, C.; Tsutani, H.; Oguma, S.; et al. Clinical importance of CD7 expression in acute myelocytic leukemia. The Japan Cooperative Group of Leukemia/Lymphoma. Blood 1993, 81, 2399–2405. [Google Scholar] [CrossRef]
  48. Chang, H.; Yeung, J.; Brandwein, J.; Yi, Q.L. CD7 expression predicts poor disease free survival and post-remission survival in patients with acute myeloid leukemia and normal karyotype. Leuk. Res. 2007, 31, 157–162. [Google Scholar] [CrossRef]
  49. Del Poeta, G.; Stasi, R.; Venditti, A.; Cox, C.; Aronica, G.; Masi, M.; Bruno, A.; Simone, M.D.; Buccisano, F.; Papa, G. CD7 expression in acute myeloid leukemia. Leuk. Lymphoma 1995, 17, 111–119. [Google Scholar] [CrossRef]
  50. Saito, T.; Usui, N.; Dobashi, N.; Maki, N.; Asai, O.; Yano, S.; Kato, A.; Watanabe, H.; Katori, M.; Nagamine, M.; et al. Prognostic significance of CD7 expression in adult acute myeloid leukemia. Rinsho Ketsueki 1998, 39, 481–486. [Google Scholar]
  51. Saxena, A.; Sheridan, D.P.; Card, R.T.; McPeek, A.M.; Mewdell, C.C.; Skinnider, L.F. Biologic and clinical significance of CD7 expression in acute myeloid leukemia. Am. J. Hematol. 1998, 58, 278–284. [Google Scholar] [CrossRef]
  52. Venditti, A.; Del Poeta, G.; Buccisano, F.; Tamburini, A.; Cox-Froncillo, M.C.; Aronica, G.; Bruno, A.; Del Moro, B.; Epiceno, A.M.; Battaglia, A.; et al. Prognostic relevance of the expression of Tdt and CD7 in 335 cases of acute myeloid leukemia. Leukemia 1998, 12, 1056–1063. [Google Scholar] [CrossRef] [PubMed]
  53. Rohrs, S.; Scherr, M.; Romani, J.; Zaborski, M.; Drexler, H.G.; Quentmeier, H. CD7 in acute myeloid leukemia: Correlation with loss of wild-type CEBPA, consequence of epigenetic regulation. J. Hematol. Oncol. 2010, 3, 15. [Google Scholar] [CrossRef] [PubMed]
  54. Gomes-Silva, D.; Atilla, E.; Atilla, P.A.; Mo, F.; Tashiro, H.; Srinivasan, M.; Lulla, P.; Rouce, R.H.; Cabral, J.M.S.; Ramos, C.A.; et al. CD7 Car T cells for the therapy of acute myeloid leukemia. Mol. Ther. 2019, 27, 272–280. [Google Scholar] [CrossRef]
  55. Dobrowolska, H.; Gill, K.Z.; Serban, G.; Ivan, E.; Li, Q.; Qiao, P.; Suciu-Foca, N.; Savage, D.; Alobeid, B.; Bhagat, G.; et al. Expression of immune inhibitory receptor ILT3 in acute myeloid leukemia with monocytic differentiation. Cytom. B Clin. Cytom. 2013, 84, 21–29. [Google Scholar] [CrossRef]
  56. John, S.; Chen, H.; Deng, M.; Gui, X.; Wu, G.; Chen, W.; Li, Z.; Zhang, N.; An, Z.; Zhang, C.C. A novel anti-lilrb4 CAR-T cell for the treatment of monocytic AML. Mol. Ther. 2018, 26, 2487–2495. [Google Scholar] [CrossRef]
  57. Ma, G.; Wang, Y.; Ahmed, T.; Zaslav, A.L.; Hogan, L.; Avila, C.; Wada, M.; Salman, H. Anti-CD19 chimeric antigen receptor targeting of CD19+acute myeloid leukemia. Leuk. Res. Rep. 2018, 9, 42–44. [Google Scholar] [CrossRef]
  58. Molldrem, J.J.; Lee, P.P.; Wang, C.; Felio, K.; Kantarjian, H.M.; Champlin, R.E.; Davis, M.M. Evidence that specific T lymphocytes may participate in the elimination of chronic myelogenous leukemia. Nat. Med. 2000, 6, 1018–1023. [Google Scholar] [CrossRef]
  59. Herrmann, A.C.; Im, J.S.; Pareek, S.; Ruiz-Vasquez, W.; Lu, S.; Sergeeva, A.; Mehrens, J.; He, H.; Alatrash, G.; Sukhumalchandra, P.; et al. A Novel T-Cell Engaging Bi-specific Antibody Targeting the Leukemia Antigen PR1/HLA-A2. Front. Immunol. 2018, 9, 3153. [Google Scholar] [CrossRef]
  60. Rafiq, S.; Purdon, T.J.; Daniyan, A.F.; Koneru, M.; Dao, T.; Liu, C.; Scheinberg, D.A.; Brentjens, R.J. Optimized T-cell receptor-mimic chimeric antigen receptor T cells directed toward the intracellular Wilms tumor 1 antigen. Leukemia 2017, 31, 1788–1797. [Google Scholar] [CrossRef]
  61. Chapuis, A.G.; Egan, D.N.; Bar, M.; Schmitt, T.M.; McAfee, M.S.; Paulson, K.G.; Voillet, V.; Gottardo, R.; Ragnarsson, G.B.; Bleakley, M.; et al. T cell receptor gene therapy targeting WT1 prevents acute myeloid leukemia relapse post-transplant. Nat. Med. 2019, 25, 1064–1072. [Google Scholar] [CrossRef] [PubMed]
  62. Leong, S.R.; Sukumaran, S.; Hristopoulos, M.; Totpal, K.; Stainton, S.; Lu, E.; Wong, A.; Tam, L.; Newman, R.; Vuillemenot, B.R.; et al. An anti-CD3/anti-CLL-1 bispecific antibody for the treatment of acute myeloid leukemia. Blood 2017, 129, 609–618. [Google Scholar] [CrossRef]
  63. Friedrich, M.; Henn, A.; Raum, T.; Bajtus, M.; Matthes, K.; Hendrich, L.; Wahl, J.; Hoffmann, P.; Kischel, R.; Kvesic, M.; et al. Preclinical characterization of AMG 330, a CD3/CD33-bispecific T-cell-engaging antibody with potential for treatment of acute myelogenous leukemia. Mol. Cancer Ther. 2014, 13, 1549–1557. [Google Scholar] [CrossRef] [PubMed]
  64. Chichili, G.R.; Huang, L.; Li, H.; Burke, S.; He, L.; Tang, Q.; Jin, L.; Gorlatov, S.; Ciccarone, V.; Chen, F.; et al. A CD3xCD123 bispecific DART for redirecting host T cells to myelogenous leukemia: Preclinical activity and safety in nonhuman primates. Sci. Transl. Med. 2015, 7, 289ra282. [Google Scholar] [CrossRef] [PubMed]
  65. Hoseini, S.S.; Guo, H.; Wu, Z.; Hatano, M.N.; Cheung, N.V. A potent tetravalent T-cell-engaging bispecific antibody against CD33 in acute myeloid leukemia. Blood Adv. 2018, 2, 1250–1258. [Google Scholar] [CrossRef] [PubMed]
  66. Reusch, U.; Harrington, K.H.; Gudgeon, C.J.; Fucek, I.; Ellwanger, K.; Weichel, M.; Knackmuss, S.H.; Zhukovsky, E.A.; Fox, J.A.; Kunkel, L.A.; et al. Characterization of CD33/CD3 tetravalent bispecific tandem diabodies (tandabs) for the treatment of acute myeloid leukemia. Clin. Cancer Res. 2016, 22, 5829–5838. [Google Scholar] [CrossRef]
  67. Harrington, K.H.; Gudgeon, C.J.; Laszlo, G.S.; Newhall, K.J.; Sinclair, A.M.; Frankel, S.R.; Kischel, R.; Chen, G.; Walter, R.B. The broad anti-aml activity of the CD33/CD3 bite antibody construct, AMG 330, is impacted by disease stage and risk. PLoS ONE 2015, 10, e0135945. [Google Scholar] [CrossRef]
  68. Laszlo, G.S.; Gudgeon, C.J.; Harrington, K.H.; Dell’Aringa, J.; Newhall, K.J.; Means, G.D.; Sinclair, A.M.; Kischel, R.; Frankel, S.R.; Walter, R.B. Cellular determinants for preclinical activity of a novel CD33/CD3 bispecific T-cell engager (BiTE) antibody, AMG 330, against human AML. Blood 2014, 123, 554–561. [Google Scholar] [CrossRef]
  69. Arndt, C.; von Bonin, M.; Cartellieri, M.; Feldmann, A.; Koristka, S.; Michalk, I.; Stamova, S.; Bornhauser, M.; Schmitz, M.; Ehninger, G.; et al. Redirection of T cells with a first fully humanized bispecific CD33-CD3 antibody efficiently eliminates AML blasts without harming hematopoietic stem cells. Leukemia 2013, 27, 964–967. [Google Scholar] [CrossRef]
  70. Westervelt, P.; Roboz, G.; Cortes, J.; Altman, J.; Oehler, V.; Long, M.; Kantarjian, H.; Lee, S.; Han, T.; Guenot, J.; et al. Safety and clinical activity of AMV564, a CD33/CD3 T-cell engager, in patients with relapsed/refractory acute myeloid leukemia (AML): Updated results from the phase I first-in-human trial. HemaSphere 2019, 3, 393–394. [Google Scholar] [CrossRef]
  71. Al-Hussaini, M.; Rettig, M.P.; Ritchey, J.K.; Karpova, D.; Uy, G.L.; Eissenberg, L.G.; Gao, F.; Eades, W.C.; Bonvini, E.; Chichili, G.R.; et al. Targeting CD123 in acute myeloid leukemia using a T-cell-directed dual-affinity retargeting platform. Blood 2016, 127, 122–131. [Google Scholar] [CrossRef] [PubMed]
  72. Lu, H.; Zhou, Q.; Deshmukh, V.; Phull, H.; Ma, J.; Tardif, V.; Naik, R.R.; Bouvard, C.; Zhang, Y.; Choi, S.; et al. Targeting human C-type lectin-like molecule-1 (CLL1) with a bispecific antibody for immunotherapy of acute myeloid leukemia. Angew Chem. Int. Ed. Engl. 2014, 53, 9841–9845. [Google Scholar] [CrossRef] [PubMed]
  73. Van Loo, P.F.; Hangalapura, B.N.; Thordardottir, S.; Gibbins, J.D.; Veninga, H.; Hendriks, L.J.A.; Kramer, A.; Roovers, R.C.; Leenders, M.; de Kruif, J.; et al. MCLA-117, a CLEC12AxCD3 bispecific antibody targeting a leukaemic stem cell antigen, induces T cell-mediated AML blast lysis. Expert Opin. Biol. Ther. 2019, 19, 721–733. [Google Scholar] [CrossRef]
  74. Durben, M.; Schmiedel, D.; Hofmann, M.; Vogt, F.; Nubling, T.; Pyz, E.; Buhring, H.J.; Rammensee, H.G.; Salih, H.R.; Grosse-Hovest, L.; et al. Characterization of a bispecific FLT3 X CD3 antibody in an improved, recombinant format for the treatment of leukemia. Mol. Ther. 2015, 23, 648–655. [Google Scholar] [CrossRef]
  75. DeRenzo, C.; Gottschalk, S. Genetic modification strategies to enhance CAR T cell persistence for patients with solid tumors. Front. Immunol. 2019, 10, 218. [Google Scholar] [CrossRef]
  76. Arcangeli, S.; Rotiroti, M.C.; Bardelli, M.; Simonelli, L.; Magnani, C.F.; Biondi, A.; Biagi, E.; Tettamanti, S.; Varani, L. Balance of anti-CD123 chimeric antigen receptor binding affinity and density for the targeting of acute myeloid leukemia. Mol. Ther. 2017, 25, 1933–1945. [Google Scholar] [CrossRef]
  77. Tasian, S.K.; Kenderian, S.S.; Shen, F.; Ruella, M.; Shestova, O.; Kozlowski, M.; Li, Y.; Schrank-Hacker, A.; Morrissette, J.J.D.; Carroll, M.; et al. Optimized depletion of chimeric antigen receptor T cells in murine xenograft models of human acute myeloid leukemia. Blood 2017, 129, 2395–2407. [Google Scholar] [CrossRef]
  78. Thokala, R.; Olivares, S.; Mi, T.; Maiti, S.; Deniger, D.; Huls, H.; Torikai, H.; Singh, H.; Champlin, R.E.; Laskowski, T.; et al. Redirecting specificity of T cells using the sleeping beauty system to express chimeric antigen receptors by mix-and-matching of VL and VH domains targeting CD123+ tumors. PLoS ONE 2016, 11, e0159477. [Google Scholar] [CrossRef]
  79. Cartellieri, M.; Feldmann, A.; Koristka, S.; Arndt, C.; Loff, S.; Ehninger, A.; von Bonin, M.; Bejestani, E.P.; Ehninger, G.; Bachmann, M.P. Switching CAR T cells on and off: A novel modular platform for retargeting of T cells to AML blasts. Blood Cancer J. 2016, 6, e458. [Google Scholar] [CrossRef]
  80. Zhou, L.; Liu, X.; Wang, X.; Sun, Z.; Song, X.T. CD123 redirected multiple virus-specific T cells for acute myeloid leukemia. Leuk. Res. 2016, 41, 76–84. [Google Scholar] [CrossRef]
  81. Gill, S.; Tasian, S.K.; Ruella, M.; Shestova, O.; Li, Y.; Porter, D.L.; Carroll, M.; Danet-Desnoyers, G.; Scholler, J.; Grupp, S.A.; et al. Preclinical targeting of human acute myeloid leukemia and myeloablation using chimeric antigen receptor-modified T cells. Blood 2014, 123, 2343–2354. [Google Scholar] [CrossRef]
  82. Pizzitola, I.; Anjos-Afonso, F.; Rouault-Pierre, K.; Lassailly, F.; Tettamanti, S.; Spinelli, O.; Biondi, A.; Biagi, E.; Bonnet, D. Chimeric antigen receptors against CD33/CD123 antigens efficiently target pirmary acute myeloid leukemia cells in vivo. Leukemia 2014, 28, 1596–1605. [Google Scholar] [CrossRef]
  83. Mardiros, A.; Dos Santos, C.; McDonald, T.; Brown, C.E.; Wang, X.; Budde, L.E.; Hoffman, L.; Aguilar, B.; Chang, W.C.; Bretzlaff, W.; et al. T cells expressing CD123-specific chimeric antigen receptors exhibit specific cytolytic effector functions and antitumor effects against human acute myeloid leukemia. Blood 2013, 122, 3138–3148. [Google Scholar] [CrossRef] [PubMed]
  84. Tettamanti, S.; Marin, V.; Pizzitola, I.; Magnani, C.F.; Giordano Attianese, G.M.; Cribioli, E.; Maltese, F.; Galimberti, S.; Lopez, A.F.; Biondi, A.; et al. Targeting of acute myeloid leukaemia by cytokine-induced killer cells redirected with a novel CD123-specific chimeric antigen receptor. Br. J. Haematol. 2013, 161, 389–401. [Google Scholar] [CrossRef] [PubMed]
  85. Budde, L.; Song, J.; Kim, Y.; Blanchard, S.; Wagner, J.; Stein, A.; AWeng, L.; Del Real, M.; Hernandez, R.; Marucci, E.; et al. Remissions of acute myeloid leukemia and blastic plasmacytoid dendritic cell neoplasm following treatment with CD123-specific CAR T cells: A first-in-human clinical trial. Blood 2017, 130, 811. [Google Scholar]
  86. Wang, Q.; Wang, Y.; Lv, H.; Han, Q.; Fan, H.; Guo, B.; Wang, L.; Han, W. Treatment of CD33-directed chimeric antigen receptor-modified T cells in one patient with relapsed and refractory acute myeloid leukemia. Mol. Ther. 2015, 23, 184–191. [Google Scholar] [CrossRef]
  87. Li, S.; Tao, Z.; Xu, Y.; Liu, J.; An, N.; Wang, Y.; Xing, H.; Tian, Z.; Tang, K.; Liao, X.; et al. CD33-specific chimeric antigen receptor T cells with different co-stimulators showed potent anti-leukemia efficacy and different phenotype. Hum. Gene Ther. 2018, 29, 626–639. [Google Scholar] [CrossRef]
  88. Minagawa, K.; Jamil, M.O.; Al-Obaidi, M.; Pereboeva, L.; Salzman, D.; Erba, H.P.; Lamb, L.S.; Bhatia, R.; Mineishi, S.; Di Stasi, A. In vitro pre-clinical validation of suicide gene modified anti-CD33 redirected chimeric antigen receptor T-cells for acute myeloid leukemia. PLoS ONE 2016, 11, e0166891. [Google Scholar] [CrossRef]
  89. O’Hear, C.; Heiber, J.; Schubert, I.; Fey, G.; Geiger, T. Anti-CD33 chimeric antigen receptor targeting of acute myeloid leukemia. Haematologica 2015, 100, 336–344. [Google Scholar] [CrossRef]
  90. Dutour, A.; Marin, V.; Pizzitola, I.; Valsesia-Wittmann, S.; Lee, D.; Yvon, E.; Finney, H.; Lawson, A.; Brenner, M.; Biondi, A.; et al. In Vitro and In Vivo Antitumor Effect of Anti-CD33 Chimeric Receptor-Expressing EBV-CTL against CD33 Acute Myeloid Leukemia. Adv. Hematol. 2012, 2012, 683065. [Google Scholar] [CrossRef]
  91. Kim, M.Y.; Yu, K.R.; Kenderian, S.S.; Ruella, M.; Chen, S.; Shin, T.H.; Aljanahi, A.A.; Schreeder, D.; Klichinsky, M.; Shestova, O.; et al. Genetic inactivation of CD33 in hematopoietic stem cells to enable CAR T cell immunotherapy for acute myeloid leukemia. Cell 2018, 173, 1439–1453. [Google Scholar] [CrossRef] [PubMed]
  92. Murad, J.M.; Baumeister, S.H.; Werner, L.; Daley, H.; Trebeden-Negre, H.; Reder, J.; Sentman, C.L.; Gilham, D.; Lehmann, F.; Snykers, S.; et al. Manufacturing development and clinical production of NKG2D chimeric antigen receptor-expressing T cells for autologous adoptive cell therapy. Cytotherapy 2018, 20, 952–963. [Google Scholar] [CrossRef]
  93. Sallman, D.A.; Brayer, J.; Sagatys, E.M.; Lonez, C.; Breman, E.; Agaugue, S.; Verma, B.; Gilham, D.E.; Lehmann, F.F.; Davila, M.L. NKG2D-based chimeric antigen receptor therapy induced remission in a relapsed/refractory acute myeloid leukemia patient. Haematologica 2018, 103, e424–e426. [Google Scholar] [CrossRef]
  94. Laborda, E.; Mazagova, M.; Shao, S.; Wang, X.; Quirino, H.; Woods, A.K.; Hampton, E.N.; Rodgers, D.T.; Kim, C.H.; Schultz, P.G.; et al. Development of A chimeric antigen receptor targeting C-type lectin-like molecule-1 for human acute myeloid leukemia. Int. J. Mol. Sci. 2017, 18, 2259. [Google Scholar] [CrossRef] [PubMed]
  95. Liu, F.; Cao, Y.; Pinz, K.; Ma, Y.; Wada, M.; Chen, K. First-in-human CLL1-CD33 compound CAR T cell therapy induces complete remission in patients with refractory acute myeloid leukemia: Update on phase 1 clinical trial. Blood 2018, 132, 901. [Google Scholar] [CrossRef]
  96. Wang, Y.; Xu, Y.; Li, S.; Liu, J.; Xing, Y.; Xing, H.; Tian, Z.; Tang, K.; Rao, Q.; Wang, M.; et al. Targeting FLT3 in acute myeloid leukemia using ligand-based chimeric antigen receptor-engineered T cells. J. Hematol. Oncol. 2018, 11, 60. [Google Scholar] [CrossRef]
  97. Jetani, H.; Garcia-Cadenas, I.; Nerreter, T.; Thomas, S.; Rydzek, J.; Meijide, J.B.; Bonig, H.; Herr, W.; Sierra, J.; Einsele, H.; et al. CAR T-cells targeting FLT3 have potent activity against FLT3(-)ITD(+) AML and act synergistically with the FLT3-inhibitor crenolanib. Leukemia 2018, 32, 1168–1179. [Google Scholar] [CrossRef]
  98. Reiter, K.; Polzer, H.; Krupka, C.; Maiser, A.; Vick, B.; Rothenberg-Thurley, M.; Metzeler, K.H.; Dorfel, D.; Salih, H.R.; Jung, G.; et al. Tyrosine kinase inhibition increases the cell surface localization of FLT3-ITD and enhances FLT3-directed immunotherapy of acute myeloid leukemia. Leukemia 2018, 32, 313–322. [Google Scholar] [CrossRef]
  99. Krawczyk, E.; Zolov, S.N.; Huang, K.; Bonifant, C.L. T-cell Activity against AML Improved by Dual-Targeted T Cells Stimulated through T-cell and IL7 Receptors. Cancer Immunol. Res. 2019, 7, 683–692. [Google Scholar] [CrossRef]
  100. Bonifant, C.L.; Szoor, A.; Torres, D.; Joseph, N.; Velasquez, M.P.; Iwahori, K.; Gaikwad, A.; Nguyen, P.; Arber, C.; Song, X.T.; et al. CD123-Engager T Cells as a Novel Immunotherapeutic for Acute Myeloid Leukemia. Mol. Ther. 2016, 24, 1615–1626. [Google Scholar] [CrossRef]
  101. Velasquez, M.P.; Szoor, A.; Vaidya, A.; Thakkar, A.; Nguyen, P.; Wu, M.F.; Liu, H.; Gottschalk, S. CD28 and 41BB costimulation enhances the effector function of CD19-specific engager T cells. Cancer Immunol. Res. 2017, 5, 860–870. [Google Scholar] [CrossRef] [PubMed]
  102. Aliperta, R.; Cartellieri, M.; Feldmann, A.; Arndt, C.; Koristka, S.; Michalk, I.; von Bonin, M.; Ehninger, A.; Bachmann, J.; Ehninger, G.; et al. Bispecific antibody releasing-mesenchymal stromal cell machinery for retargeting T cells towards acute myeloid leukemia blasts. Blood Cancer J. 2015, 5, e348. [Google Scholar] [CrossRef] [PubMed]
  103. Aliperta, R.; Welzel, P.B.; Bergmann, R.; Freudenberg, U.; Berndt, N.; Feldmann, A.; Arndt, C.; Koristka, S.; Stanzione, M.; Cartellieri, M.; et al. Cryogel-supported stem cell factory for customized sustained release of bispecific antibodies for cancer immunotherapy. Sci. Rep. 2017, 7, 42855. [Google Scholar] [CrossRef] [PubMed]
  104. Zhang, J.; Hu, X.; Wang, J.; Sahu, A.D.; Cohen, D.; Song, L.; Ouyang, Z.; Fan, J.; Wang, B.; Fu, J.; et al. Immune receptor repertoires in pediatric and adult acute myeloid leukemia. Genome Med. 2019, 11, 73. [Google Scholar] [CrossRef]
  105. Xue, L.; Hu, Y.; Wang, J.; Liu, X.; Wang, X. T cells targeting multiple tumor-associated antigens as a postremission treatment to prevent or delay relapse in acute myeloid leukemia. Cancer Manag. Res. 2019, 11, 6467–6476. [Google Scholar] [CrossRef]
  106. Lee, D.W.; Santomasso, B.D.; Locke, F.L.; Ghobadi, A.; Turtle, C.J.; Brudno, J.N.; Maus, M.V.; Park, J.H.; Mead, E.; Pavletic, S.; et al. ASTCT consensus grading for cytokine release syndrome and neurologic toxicity associated with immune effector cells. Biol. Blood Marrow Transplant. 2019, 25, 625–638. [Google Scholar] [CrossRef]
  107. Shimabukuro-Vornhagen, A.; Godel, P.; Subklewe, M.; Stemmler, H.J.; Schlosser, H.A.; Schlaak, M.; Kochanek, M.; Boll, B.; von Bergwelt-Baildon, M.S. Cytokine release syndrome. J. Immunother. Cancer 2018, 6, 56. [Google Scholar] [CrossRef]
  108. Orlando, E.J.; Han, X.; Tribouley, C.; Wood, P.A.; Leary, R.J.; Riester, M.; Levine, J.E.; Qayed, M.; Grupp, S.A.; Boyer, M.; et al. Genetic mechanisms of target antigen loss in CAR19 therapy of acute lymphoblastic leukemia. Nat. Med. 2018, 24, 1504–1506. [Google Scholar] [CrossRef]
  109. Gardner, R.; Finney, O.; Annesley, C.; Brakke, H.; Summers, C.; Leger, K.; Bleakley, M.; Brown, C.; Mgebroff, S.; Kelly-Spratt, K.; et al. Intent-to-treat leukemia remission by CD19 CAR T cells of defined formulation and dose in children and young adults. Blood 2017, 129, 3322–3331. [Google Scholar] [CrossRef]
  110. Klco, J.M.; Spencer, D.H.; Miller, C.A.; Griffith, M.; Lamprecht, T.L.; O’Laughlin, M.; Fronick, C.; Magrini, V.; Demeter, R.T.; Fulton, R.S.; et al. Functional heterogeneity of genetically defined subclones in acute myeloid leukemia. Cancer Cell 2014, 25, 379–392. [Google Scholar] [CrossRef]
  111. Petrov, J.C.; Wada, M.; Pinz, K.G.; Yan, L.E.; Chen, K.H.; Shuai, X.; Liu, H.; Chen, X.; Leung, L.H.; Salman, H.; et al. Compound CAR T-cells as a double-pronged approach for treating acute myeloid leukemia. Leukemia 2018, 32, 1317–1326. [Google Scholar] [CrossRef] [PubMed]
  112. Lamble, A.J.; Lind, E.F. Targeting the Immune Microenvironment in Acute Myeloid Leukemia: A Focus on T Cell Immunity. Front. Oncol. 2018, 8, 213. [Google Scholar] [CrossRef] [PubMed]
  113. Szczepanski, M.; Szajnik, M.; Czystowska, M.; Mandapathil, M.; Strauss, L.; Welsh, A.; Foon, K.; Whiteside, T.; Boyiadzis, M. Increased frequency and suppression by regulatory T cells in patients with acute myelogenous leukemia. Clin. Cancer Rev. 2009, 15, 3325–3332. [Google Scholar] [CrossRef] [PubMed]
  114. Zhou, Q.; Bucher, C.; Munger, M.; Highfill, S.; Tolar, J.; Munn, D.; Levine, B.; Riddle, M.; June, C.; Vallera, D.; et al. Depletion of endogenous tumor-associated regulatory T cells improves the efficacy of adoptive cytotoxic T-cell immunotherapy in murine acute myeloid leukemia. Blood 2009, 114, 3793–3802. [Google Scholar] [CrossRef]
  115. Pyzer, A.; Stroopinsky, D.; Rajabi, H.; Washington, A.; Tagde, A.; Coll, M.; Fung, J.; Bryant, M.; Cole, L.; Palmer, K.; et al. MUC1-mediated induction of myeloid-derived suppressor cells in patients with acute myeloid leukemia. Blood 2017, 129, 1791–1801. [Google Scholar] [CrossRef]
  116. Sun, H.; Li, Y.; Zhang, Z.; Ju, Y.; Li, L.; Zhang, B.; Liu, B. Increase in myeloid-derived suppressor cells (MDSCs) associated with minimal residual disease (MRD) detection in adult acute myeloid leukemia. Int. J. Hematol. 2015, 102, 579–586. [Google Scholar] [CrossRef]
  117. Rickmann, M.; Macke, L.; Sundarasetty, B.; Stamer, K.; Figueiredo, C.; Blasczyk, R.; Heuser, M.; Krauter, J.; Ganser, A.; Stripecke, R. Monitoring dendritic cell and cytokine biomarkersduring remission prior to relapse in patients with FLT3-ITD acute myeloid leukemia. Ann. Hematol. 2013, 92, 1079–1090. [Google Scholar] [CrossRef]
  118. Han, Y.; Dong, Y.; Yang, Q.; Xu, W.; Jiang, S.; Yu, Z.; Yu, K.; Zhang, S. Acute myeloid leukemia cells express ICOS ligand to promote the expansion of regulatory T cells. Front. Immunol. 2018, 9, 2227. [Google Scholar] [CrossRef]
  119. Nabe, S.; Yamada, T.; Suzuki, J.; Toriyama, K.; Yasuoka, T.; Kuwahara, M.; Shiraishi, A.; Takenaka, K.; Yasukawa, M. Reinforce the antitumor activity of CD8+ T cells via glutamine restriction. Cancer Sci. 2018, 12, 3737–3750. [Google Scholar] [CrossRef]
  120. Mussai, F.; De Santo, C.; Abu-Dayyeh, I.; Booth, S.; Quek, L.; McEwen-Smith, R.; Qureshi, A.; Dazzi, F.; Vyas, P.; Cerundolo, V. Acute myeloid leukemia creates an arginase-dependent immunosuppressive microenvironment. Blood 2013, 122, 749–758. [Google Scholar] [CrossRef]
  121. Krupka, C.; Kufer, P.; Kischel, R.; Zugmaier, G.; Lichtenegger, F.S.; Kohnke, T.; Vick, B.; Jeremias, I.; Metzeler, K.H.; Altmann, T.; et al. Blockade of the PD-1/PD-L1 axis augments lysis of AML cells by the CD33/CD3 BiTE antibody construct AMG 330: Reversing a T-cell-induced immune escape mechanism. Leukemia 2016, 30, 484–491. [Google Scholar] [CrossRef] [PubMed]
  122. Gokbuget, N.; Dombret, H.; Bonifacio, M.; Reichle, A.; Graux, C.; Faul, C.; Diedrich, H.; Topp, M.S.; Bruggemann, M.; Horst, H.A.; et al. Blinatumomab for minimal residual disease in adults with B-cell precursor acute lymphoblastic leukemia. Blood 2018, 131, 1522–1531. [Google Scholar] [CrossRef] [PubMed]
  123. Ali, S.; Moreau, A.; Melchiorri, D.; Camarero, J.; Josephson, F.; Olimpier, O.; Bergh, J.; Karres, D.; Tzogani, K.; Gisselbrecht, C.; et al. Blinatumomab for acute lymphoblastic leukemia: The first bispecific T-cell engager antibody to be approved by the EMA for minimal residual disease. Oncologist 2019. [Google Scholar] [CrossRef] [PubMed]
Figure 1. Strategies to Harness T Cells for Immunotherapy of acute myeloid leukemia (AML). CAR—chimeric antigen receptor, TCR—T-cell receptor, MHC—major histocompatibility complex.
Figure 1. Strategies to Harness T Cells for Immunotherapy of acute myeloid leukemia (AML). CAR—chimeric antigen receptor, TCR—T-cell receptor, MHC—major histocompatibility complex.
Children 07 00014 g001
Table 1. Bispecific Antibody Clinical Trials for AML.
Table 1. Bispecific Antibody Clinical Trials for AML.
CD123NCT04158739Children’s Oncology Groupflotetuzumab (MGD006)<21
NCT02715011Janssen Research & Development, LLCJNJ-6370917818+
NCT02152956MacroGenicsflotetuzumab (MGD006)18+
NCT03915379Janssen Research & Development, LLCJNJ-6757124418+
NCT03516760GEMoaB Monoclonals GmbHGEM33318+
CLEC12A (CLL1)NCT03038230Merus N. V.MCLA-11718+
Summary of active clinical trials according to as of 12/18/19.
Table 2. CAR T-cell clinical trials for AML.
Table 2. CAR T-cell clinical trials for AML.
United States
CD123NCT02159495City of Hope Medical Center12+
NCT03766126University of Pennsylvania18+
NCT04109482Mustang Bio18+
NCT03190278Cellectis S. A.18–64
pendingSt. Jude Children’s Research Hospital<21
CD33NCT03971799Center for International Blood and Marrow Transplant Research (National Cancer Institute, Children’s Hospital of Philadelphia)1–30
CD123NCT03556982Affiliated Hospital of the Chinese Academy of Military Medical Sciences, China14–75
NCT03796390Hebei Senlang Biotechnology, China2–65
NCT04014881Wuhan Union Hospital, China18–70
NCT03114670Affiliated Hospital to Academy of Military Medical Sciences, China18+
NCT04106076Cellectis S. A., United Kingdom
CD7NCT04033302Shenzhen Geno-Immune Medical Institute, China6 mos-75
CD44v6NCT04097301MolMed, Horizon 2020, ItalyI: 18–75
II: 1–75
Lewis YNCT01716364Peter MacCallum Cancer Center, Australia18+
CD19NCT03896854Shanghai Unicar-Therapy Bio-medicine Technology Co, Ltd., China
CD123/CLL1NCT03631576Fujian Medical University, China<70
CD123/CD33NCT04156256iCell Gene Therapeutics, Chinachild, adult
CCL1/CD33/CD123NCT04010877Shenzhen Geno-Immune Medical Institute, China2–75
NCT03222674Shenzhen Geno-Immune Medical Institute, China2–75
NCT03473457Zhujiang Hospital, China6 mos+
Summary of active and completed clinical trials according to as of 12/18/19, in addition to upcoming trial at authors’ institution pending registration.
Back to TopTop